Diesel exhaust gas filter



Nov. 3, 1959 1.. E. FoRR'Y 2,911,289

DIESEL EXHAUST GAS FILTER I Filed Nov. 19, 1956 2 Sheets-Sheet 1INVENTOR.

LEONARD E. FORRY 7 replacement.

United States PatentO 2,911,289 DIESEL EXHAUST GAS FILTER Leonard E.Forry, South Haven, Mich., assignor to Getman Brothers ManufacturingDivision, Inc., South Haven, Mich., a corporation of MichiganApplication November 19, 1956, Serial No. 623,049

2 Claims. (Cl. 23-284) This invention relates in general to an apparatusand method for filtering the exhaust gases from a diesel engine and,more particularly, to a formof apparatus and method whereby the solidcarbon and objectionable odors are substantially removed from, and theorganic acids are neutralized in, the "exhaust gases produced by theoperation of a diesel engine.

It is well known that the exhaust gases of internal combustion engines,such as diesel engines, contain many noxious and deleterious components.As long as these exhaust gases can escape substantially immediately intoan unconfined free air space, no particular problem arises from theundesirable components in said exhaust gases.

However, where the engine is being operated where forced draftventilation is required, for example, underground, the undesirablecomponents in said exhaust gases become a real problem. This isparticularly true where it is desirable to have a portable engine whichcannot be advantageously connected to any type of permanent stackarrangement venting to atmosphere. These problems arise with particularfrequency in the operation of diesel engines in mines. v

In the case of'diesel engines, particularly, the amount of solid carbonand organic acids, if not properly vented or filtered, can be highlyinjurious both to personnel and equipment used within the mines. Sincethe venting of the engine exhaust gases to atmosphere is both costly andlimiting upon the operation and mobility of the diesel engine,particularly at low levels in the mine, a completely satisfactory meanshas long been sought whereby said noxious and deleterious components,such as said carbon and organic acids, can be effectively removed fromsaid exhaust gases right at the location of the diesel engine, afterwhich the remaining, unharmful components of said exhaust gases aredischarged back into the, mine shaft. Due to the deleterious componentsin the exhaust gases from diesel engines, existing mechanisms utilizedfor the purpose of filtering said exhaust gases have never beencompletely satisfactory. This lack of satisfaction has been in part dueto the fact that the organic acids in the exhaust gases will damage thematerials in the filter device, thereby necessitating frequent Wherespecial materials, substantially impervious to such deleterious attacks,have been utilized in the filtering device, the cost has been so high asto discourage widespread usage. I

It will be recognized that reference is specifically made to a mineshaft and a diesel engine for illustrative purposes, only, since theproblem which this invention seeks to overcome can arise wherever itis'desirable to operate a device emitting fumes of this generalcharacter into a relatively confined zone, which is located asubstantial distance from, or is relatively inaccessible to, free air.

Accordingly, a principal object of this invention has been the provisionof an apparatus and method for removing the harmful components, or atleast the harmful Patented Nov. 3, 1959 amounts thereof, from theexhaust gases of a device, such as a diesel engine, whereby said harmfulcomponents are removed at the location'of the diesel engine, so that theremaining components of said exhaust gases can be safely returned to theair spaced in the vicinity of said engine.

A further object of this invention has been the provision of anapparatus and method, as aforesaid, which does not materially limit themobility of the diesel engine; which does not require any type ofpermanent or temporary connection to free air or atmosphere; whichoperates automatically; which requires little or no main-,

fabricate, automatic in its operation, can be regenerated quickly andeasily, is positive in its action, and eliminates substantially all ofthe undesirable components from the exhaust fumes of a diesel engine.

Other objects and purposes of this invention will become apparent topersons familiar with this type of equipment upon reading the followingspecification and examining the accompanying drawings, in which:

Figure l is a side elevation view of a filtering apparatuscharacterizing the invention, and including a sche? matic showing of adiesel engine.

Figure 2 is a sectional view, taken along the line II-II of Figure 1.

Figure 3 is a sectional view, taken along the line HI III of Figure 2.

Figure 4 is a sectional view, taken along the line IV-IV of Figure l. I

For the purposes of convenience in description, the terms upper, lower,and derivatives thereof, will have reference to the apparatusasappearing in Figure 1.

The terms front,. rear, and derivatives thereof, will have reference tothe left and right sides, respectively, of the apparatus as appearing inFigure 1. The terms inner, outer, and derivatives thereof, will haveref- One form of apparatus 10 (Figures 1 and 2), characterizing theinvention, and by means of which the meth- 0d of this invention may becarried out, includes an enclosed casing 11, which may be fabricatedfrom sheet or plate material, such as steel. A drain plate 12 isdisposed within the casing 11 and extends from the rear wall 13 towardthe front wall 14, with a slight, gradual downslope. Said drain plate12, which is preferably disposed approximately midway between the upperwall 15 and the lower wall 16 of the casing 11, elfects a partitioningof the spaced enclosed by the casing 11 into an upper zone 17 and lowerzone 18. An exhaust gas inlet 19 extends through the rear wall 13 andcommunicates with the lower zone 18. An exhaust gas outlet 20communicates with the upper zone 17. A basic solution 22 is placed inthe lower zone 18, so that the exhaust gas inlet 19 will dischargethereinto. A filter compartment 23 is provided in the upper zone 17,through which said exhaust gases must pass when moving from said lower ADetailed construction As shown in Figures 1, 2 and 3, the casing 11 ispreferablysrectangular in shape and has, in addition to the abovementioned rear, front, upper and lower walls, a pair of end wallss25 and26. The drain plate 12 extends between, and is secured, as 'by means ofwelding, to the end walls 25 and 26 and is also secured, as by welding,to the rear wall 13. The lower, front edge 27 of the drain plate 12 isspaced from the front wall 14. A substantially vertical bafile plate 28is secured to, and extends between, the end walls 25 and 26, and extendsdownwardly from the-upper wall toward, but spaced from, the drain plate12 about midway between the front and rear edges thereof. A porouspartition 29 extends downwardly from the plate 28 and is secured, as bywelding, at its upper and lower edges to the bafile plate 28 and drainplate 12, re spectively. A porous partition 31 is secured to, andextends upwardly from, the drain plate 12 near the front edge 27 thereofand is arranged substantially parallel with the bafile plate 28 andporous partition 29 extending downwardly therefrom. The two, porouspartitions 29 and 31,

like the bafie plate 28, extend between the end walls 25 p and 26 andcombine therewith to define the filter compartment 23, the lower wall ofwhich is provided by the adjacent portion of the drain plate 12. Theporous partitions 29 and 31 are conveniently constructed from heavyscreen or from expanded metal in a conventional manner.

Flanges 32 are secured to, and extend inwardly from, the upper edges ofthe front, rear and end walls of the casing 11. A sealing member, suchas a gasket 33, is disposed between said flanges 32 and the upper wall15, which is removably mounted upon said flanges by means of the bolts34.

The exhaust gas outlet is supported upon the upper wall 15 andcommunicates through an opening therein with the upper zone 17 betweenthe baflle plate 28 and the rear wall 13.

The exhaust gas inlet 19, which may be connected to the exhaust pipe 35of the diesel engine 24 through a check valve 36, extends, in thisparticular embodiment, through the rear wall 13 into the upper zone 17and then downwardly into the lower zone 18 through an appropriateopening in the drain plate 12. The lower end of said exhaust gas inlet19 is connected to a horizontally disposed, dispersing pipe 37 whichextends between, and is supported" upon, the end walls and 26. Clean-outplugs 38, which are accessible from the exterior of said casing 11, areremovably disposed within the ends of said dispersing pipe 37. Said pipe37, which is located near to, but spaced from, the lower wall 16, isprovided with a plurality of ports 39 through which the exhaust fumesconducted by the exhaust gas inlet 19 may escape into the lower zone 18.The exhaust gas inlet 19 is provided with a clean-out plug 41 at itsupper end within the casing 11 and accessible when the upper wall 15 isremoved from said casing.

The end wall 26 is provided with a removable filler plug 42 adjacent to,and just below, the front edge 27 of the drain plate 12. A removabledrain plug 43 is provided in said end wall 26 near the lower edgethereof. 7

In this particular embodiment of the invention, the lower zone '18 ofthe casing 11 is filled with water up to the lower edge of the fillerplug 42, as shown in Figure 3. Lime rock 44 is placed in the lower zone18, hence in the lower end of the casing'll, up to a level which isapproximately midway between the filler plug 42 and the bottom wall 16,thereby covering, or substantially covering, the dispersing pipe 37. Thewater combines with the lime rock 44 to provide a basic solution 22.Lime rock 44 is also placed within the filter compartment 23, so that itextends at least above the lower edge of the baffle plate 28,and'conipletely between the end walls 25- and 26.

partrnent 23, before discharging through the exhaust gas outlet 20.

The liquid capacity of the lower zone 18, hence the distance between thefiller plug 42 and bottom wall 16, appears to depend in part upon thesize and horsepower of the diesel engine with which the apparatus 10 isintended to operate. In one installation involving a 60 horsepowerengine, it was found that the filter 10 would operate satisfactorily forabout one day when the lower zone contained about 24 gallons of waterand was about half full of lime rock derived from Indiana limestone.This result suggested an operating proportion of about one gallon ofwater to 2.5 horsepower.

Operation Before using the apparatus described hereinabove for thepurpose of carrying out the method of this invention, the upper wall 15is removed from the casing 11 so that lime rock may be placed in thefilter compartment 23 and in the lower zone 18 adjacent to the lowerwall 16; The upper wall 15 is then replaced on the casing l land."

secured in position by means of the bolts 34. The filler plug 42 isremoved, the lower zone 18 is filled with water.

is connected to the exhaust pipe 35 of said diesel engine 24 and theapparatus 10 is ready for operation.

When the diesel engine 24 is operating, the exhaust fumes therefrom willpass through the exhaust pipe 35 and exhaust gas inlet 19 to thedispersing pipe 37, where they will escape through the ports 39 andbubble up through the basic solution 22. The water in said. solution:etfectively captures the free carbon in the engine exhaust fumes.Certain components of said exhaust fumes tend to produce an acidsolution as they mix with the water in the lower zone 18. However, thesolution 22 created by the lime rock immediately neutralizes any suchtendency. Thus, any water vapor which moves upwardly with the exhaustgases emitted from the lower zone will be substantially non-acidic. Thisis very important because it permits the use of ordinary ferrous metals,such as steel plate, in the apparatus, thereby greatly reducing the costof its fabrication.

The gases escaping from. the lower zone 18 pass up wardly between thefront wall 14 and the adjacent edge 27 of the drain plate 12 into theupper zone 17. Said gases then pass through the porous partition 31 intothe filter compartment 23 containing more lime rock.

said gases pass through the lime rock in the filter com.- partment 2.3,va substantial portion of the water vapor therein is deposited upon thelime rock, after which said gases, less said deposited water vapor, passthrough the porous partition 29 and then discharge through the exhaustgas outlet 20. The gases thus discharged from the outlet 20 arerelatively odorless and harmless. Normally, they actually constitutelittle more than warm air. Analysis of the exhaust fumes before andafter passing through the filter 10 indicates that it removes all butimmaterial amounts of the undesirable components in the plate 12 untilthey run over the front .edge 27 thereof back into the lower zone 13. Inlime rock in the lower zone 18 prevents the formation of an acidsolution in the water which is utilized to absorb the carbon in theexhaust fumes. The lime rock in the upper zone 17 is believed tofunction partly as a filter, partly as an absorbent and partly as aneutralizing agent. The lime rock in said upper zone 17 serves to removemuch of the water vapor from the gases passing therethrough.

By having the upper portion of the exhaust gas inlet 19 pass through theupper zone 17, the gases passing between the compartment 23 and theexhaust outlet 20 will circulate around said gas inlet 19, therebytending to cool the exhaust fumes passing therethrough.

Under normal conditions of operation, the water in the lower zone 18 isreplaced after each day of operation by manipulation of the plugs 42 and43 in a conventional manner. The lime rock in the lower zone 18 isregenerated after approximately 50 hours of operation of the apparatus10, by placing a relatively small amount, such as a handful, of slakedlime into the solution 22. This is accomplished by removing the upperwall 15, or more easily, the filler plug 42. Regeneration, in thisparticular instance, amounts to removal of the deposits on the limerock, which occur as a result of, and are produced by, certainundesirable components in the exhaust fumes from said diesel engine 24.The cleansing eifect of the slaked lime is carried up to the lime rockin the upper zone 17 by the water vapor moving through the filtercompartment 23 during succeeding operation of the apparatus followingthe application of said slaked lime to the solution 22. However, undercircumstances of severe operation, it may be necessary to treat the limerock in the upper zone 17 with an independent supply of slaked lime.

The dispersing pipe 37 and exhaust inlet pipe 19 may be cleaned byremoving the clean-out plugs 38 and 41, respectively. For convenience inoperation, the apparatus 10 and diesel engine 24 associated therewithmay be mounted upon a single supporting device, not shown, for thepurpose of moving the two units simultaneously from one location toanother. Because the filter apparatus 10 substantially eliminates theharmful components from the exhaust fumes of the diesel engine saidexhaust gas outlet may discharge the gases from the casing 11 directlyinto the air surrounding the apparatus 10.

It has been found that either lime rock (CaCO or dolomite (MgCO CaCO canbe used to produce substantially the same satisfactory results.Furthermore, it appears that certain other carbonate salts andhydroxides of monovalent and bi-valent alkaline metals, such as bakingsoda (NaHCO and sodium hydroxide (NaOH), can be utilized, but often withvarying degrees of success in that they were found generally to workqualitatively but were less desirable quantitatively. Thus, thecarbonate salts of the alkaline earth metals with the lower atomicnumbers appear to produce the most desirable results.

Although a particular, preferred embodiment of the invention has beendescribed hereinabove for illustrative purposes, it will be recognizedthat variations or modifications thereof, which do not depart from thesubstance of such description, are fully contemplated unlessspecifically stated to the contrary in the appended claims.

I claim:

1. A device for purifying the exhaust gases of a diesel enginecomprising: a closed casing having a quantity of water in the lowerportion thereof and a first bed of broken lime rock submerged in saidquantity of water; an elongated inlet pipe extending transversely ofsaid casing in the lower portion thereof and submerged in said quantityof water and received within said first bed and having axially spacedapertures therethrough through which exhaust gases may pass; a planar,imperforate plate fixed to said casing above said quantity of water,said plate extending part way across said casing so as to define apassage between the free edge thereof and the opposing wall of saidcasing for gases exiting from said quantity of water, said plate beingsloped downwardly with said free edge thereof being lowermost so thatwater vapor collecting thereon will drain downwardly into said quantityof water; a pair of transversely spaced perforate partitions extendingupwardly from said plate and a second bed of broken lime rock beingreceived therebetween, the partition remote from said free edge of saidplate having an imperforate portion extending upwardly from below theupper surface of said second bed to the top wall of said casing, gasespassing upwardly through said passage also passing through saidpartitions and said second bed into a compartment located between saidremote partition and the adjacent side and top walls of said casmg; andan outlet conduit communicating with said compartment whereby purifiedexhaust gases may exit therefrom.

2. A device for purifying the exhaust gas of a diesel engine comprising:a closed rectangular casing having a quantity of water in the lowerportion thereof and a first bed of broken lime rock resting on thebottom wall of ,said casing submerged in said quantity of water; an

elongated inlet pipe extending transversely of said casing between theside walls thereof, said inlet pipe being adjacent the bottom wall ofsaid casing and submerged in said quantity of water and received withinsaid bed, said inlet pipe having a series of axially spaced aperturestherethrough through which exhaust gases may pass into said quantity ofwater; a planar, imperforate drain plate secured to said casing abovesaid quantity of water and extending part way thereacross, said platesloping toward the bottom of said casing so that the free edge thereofis lowermost, said free edge and said casing defining a passage forupward movement of the gases between the free edge and the opposing wallof said casing; a first perforate partition extending upwardly from saidplate adjacent the free edge thereof substantially to the top or sa1dcasing; a second partition extending upwardly from said plate and beingspaced transversely from said first partition, said second partitionincluding a first perforate portion located adjacent said plate and asecond imperforate portion extending from the upper edge of said firstportion to the upper wall of said casing; a second bed of broken limerock confined between said first and second partitions and resting onsaid plate, said bed extending above the upper edge of said firstportion of said second partition so that exhaust gases pass through saidsecond bed as they move between said first and second partitions; theuppermost portion of said plate, said second partition and the adjacentwalls of said casing defining a compartment in the upper portion of saidcasing into which exhaust gases move after passing through said secondbed; and an outlet conduit communieating with said compartment wherebypurified exhaust gases may exit therefrom.

References Cited in the file of this patent UNITED STATES PATENTS2,611,680 Ruth Sept. 23, 1952 2,677,601 Ruth May 4, 1954 2,785,962 RuthMar. 19, 1957 2,789,032 Bagley et a1. Apr, 16, 1957

1. A DEVICE FOR PURIFYING THE EXHAUST GASES OF A DIESEL ENGINECOMPRISING: A CLOSED CASING HAVING A QUANTITY OF WATER IN THE LOWERPORTION THEREOF AND A FIRST BED OF BROKEN LIME ROCK SUBMERGED IN SAIDQUANTITY OF WATER; AN ELONGATED INLET PIPE EXTENDINGTRANSVERSELY OF SAIDCASING IN THE LOWER PORTION THEREOF AND SUBSMERGED IN SAID QUANTITY OFWATER AND RECEIVED WITHIN SAID FIRST BED AND HAVING AXIALLY SPACEDAPERTURES THERETHROUGH THROUGH WHICH EXHAUST GASES MAY PASS; A PLANAR,IMPERFORATE PLATE FIXED TO SAID CASING ABOVE SAID QUANTITY OF WATER,SAID PLATE EXTENDING PART WAY ACROSS SAID CASING SO AS TO DEFINE APASSAGE BETWEEN THE FREE EDGE THEREOF AND THE OPPOSING WALL OF SAIDCASING FOR GASES EXITING FROM SAID QUANTITY OF WATER, SAID PLATE BEINGSLOPED DOWNWARDLY WITH SAID FREE EDGE THEREOF BEING LOWERMOST DOT THATWATER VAPOR COLLECTING THEREON WILL DRAIN DOWNWARDLY INTO SAID QUANTITYOF WATER, A PAIR OF TRANSVERSELY SPACED PERFORATE